When adding images to a Widget background or a Media card within a Widget, you can edit how it fits that space using the toolbar.
For Widget backgrounds, the toolbar is located in the top left. Click the Background image tab, and here you have different options for Image Fit.
Auto Fit
Fit within Space
Scale
Remove image - use a colour background instead
The Edit feature allows us to zoom in or out of the image, rotate, and toggle aspect ratio.
For Images within a Media card, click the image, then choose Image Settings. The same Fit options will be there, an image size slider, image shape options, and also the image editor.
Additionally, when an image is embedded using the new text editor, you can resize an image by using the two black bars that appears by the images sides, just hold and adjust to your preference.
Watch this video to know how to embed images and videos and change their sizes through the text editor!